Apparatus for recognition of objects, such as human hand shapes, using image processing techniques is well known in the art, and several prior art systems exist which aim to recognize, e.g. different hand gestures, by using cameras and electronic processing apparatus. In such prior art systems, the pictures of objects are typically captured in front of a complicated background or a background of a fixed color. However, different objects might have different colors (e.g. due to different skin colors). If the color of the object is close to that of the background, it is difficult to provide accurate and stable recognition in the prior art systems. Because of this, these prior art systems have limited applications in the fields where high accuracy and good stability are required.
Therefore, it is needed to provide a technique for detecting and analyzing an object, such as human hands, with high accuracy and good stability.